Because of environmental and other advantages associated with them, linerless labels are becoming increasingly more popular. Linerless labels are typically sold in rolls of continuous labels, with or without perforations or other lines of weakness between the labels, or in stacks. Each type of configuration has its own associated advantages and disadvantages, one of the most significant disadvantages associated with conventional rolls of linerless labels being the need to have a dispenser which can facilitate separation of the labels as they are being dispensed.
According to the present invention a method and apparatus are provided for forming a roll of linerless labels that has a different configuration than conventional rolls. The rolls formed according to the invention are composed of shingled, distinct linerless labels. In this configuration most of the advantages of a roll are still available but there is no necessity to provide a device for facilitating separation of the labels where dispensed since the labels are already distinct from each other.
The apparatus according to the present invention uses simple primarily standard components to form a roll of shingled, distinct linerless labels. Basically a standard rewind unit may be used in association with a standard cut off unit, with various mechanisms associated with the take-up unit to adjust its position, and with a transport conveyor operating at a particular speed between the cut off and the take-up.
According to one aspect of the present invention a method of forming a roll of shingled, distinct linerless labels is provided. The method comprises the following steps: (a) Forming a plurality of distinct linerless labels, each label comprising a substrate, a release coated first face, and a pressure sensitive adhesive coated second face. (b) Conveying the linerless labels substantially separated and distinct from each other in a first direction at a first speed. And, (c) taking up the linerless labels from step (b) on a formed roll of shingled linerless labels, by rotating the roll of linerless labels with an initial tangential velocity component in the first direction and at a second speed, slower than the first speed, so that the distinct labels overlap with the second face of each newly added linerless label engaging the first face of at least one linerless label already on the formed roll.
Typically the formed roll is rotatable about a substantially horizontal axis and has a periphery at which labels are added to the formed roll. Step (b) is practiced in a substantially linear and horizontal first direction at a first level, and there is the further step (d) of automatically moving the roll of shingled labels in response to the size of the roll so that substantially the highest point of the periphery of the formed roll is substantially at the first level. There is also typically the further step (e) of pressing each linerless label onto the formed roll immediately after each label is brought into contact with the periphery thereof.
Step (a) is typically practiced by transporting a web at a third speed, slower than the first speed and faster than the second speed, substantially in the first direction, automatically severing distinct labels from the web, and after severing accelerating the distinct linerless labels to the first speed. Step (d) is typically practiced by mounting the formed roll on a shaft, in turn mounted on at least one articulating arm mounted for pivotal movement at a pivot point remote from the shaft, sensing the highest point of the periphery of the formed roll, and pivoting the arm about the pivot point in response to the sensing. Typically the first speed is approximately 25% faster than the third speed, and the speed ratio of the second and third speeds is adjusted to provide shingled overlap of linerless labels taken up on the formed roll therebetween of about 10-90%.
According to another aspect of the present invention apparatus for forming a roll of shingled distinct elements is provided (preferably linerless labels). The apparatus comprises: A roll shaft. A pivot shaft substantially parallel to the roll shaft. At least one articulating arm connected at a first portion thereof to the roll shaft and at a second portion thereof, remote from the first portion, to the pivot shaft. Means for rotating the roll shaft about an axis of rotation. Means for selectively holding the articulating arm at a position to which it has been moved, or moving it to other positions by pivoting the arm about the pivot shaft. And, pressing means positioned generally in alignment with and adjacent the articulating arm and substantially between the roll shaft and the pivot shaft and for pressing individual distinct elements into a formed roll of shingled distinct elements.
The pressing means preferably comprises a non-driven surface belt mounted on a plurality of idler rollers substantially to the roll shaft and pivot shaft. Alternatively the pressing means could comprise spring pressed rollers, a relatively stationary smooth low friction surface, or other devices. The means selectively holding or moving the at least one articulating arm preferably comprises at least one piston and cylinder assembly, either hydraulic or pneumatic, most preferably a pair of pneumatic cylinders controlled by a pneumatic controller. Alternatively the arm holding or moving means may comprise a rotating or linear cam arrangement, a cog wheel, or other types of linear actuators pivoted to the articulating arm.
The roll shaft is rotated about an axis of rotation by a DC motor, or pneumatic, hydraulic, or other power source motors. Typically the motor is mounted on and movable with the articulating arm.
The apparatus typically further comprises means for delivering the distinct elements, one at a time, separated and distinct from each other between the roll shaft and the pressing means. The delivery means typically comprises a driven transport conveyor belt. The apparatus typically further comprises means for severing a web into individual distinct elements positioned adjacent the delivery means, the severing means for example comprising bursters, conventional guillotine blade arrangements, or a rotating cylinder with one or more blades cooperating with an anvil roll.
The apparatus further comprises first sensing means (e.g. an optical sensor) for sensing the position of elements formed on the roll shaft, second sensing means for sensing the speed of the web prior to the severing means, and a controller (e.g. computer) receiving input from the first and second sensing means, the controller controlling the means for selectively holding or moving the articulating arm in response to the first sensing means, and for controlling the means for rotating the roll shaft about an axis of rotation in response to the second sensing means.
According to yet another aspect of the present invention apparatus for forming linerless labels into a roll of shingled distinct linerless labels, each label comprising a substrate, a release coated first face, and a pressure sensitive adhesive coated second face, is so provided. The apparatus comprises the following elements: A roll shaft. A plurality of shingled distinct linerless labels comprising a formed roll on the roll shaft, the second face of each label closer to the roll shaft than the first face thereof. A pivot shaft substantially parallel to the roll shaft. At least one articulating arm connected at a first portion thereof to the roll shaft and at a second portion thereof, remote from the first portion, to the pivot shaft. And, means for rotating the roll shaft about an axis of rotation. The components comprising this apparatus may be as described above in their preferred embodiments.
It is the primary object of the present invention to provide a method and apparatus effecting the simple and efficient formation of a roll of shingled, distinct linerless labels, or the like. This and other objects of the invention will become clear from an inspection of the detailed description of the invention and from the appended claims.